1. Field of the Invention
The present invention relates to a rotary spray nozzle for ejecting or dispersing a jet of pressurized air, liquid, and/or other medium.
2. Description of Related Art
Many devices have been used for cleaning dust and dirt from a surface. Some such devices clean a surface by spraying a gas (e.g., compressed air) from an opening of a nozzle in a cleaning device. Other devices clean a surface by forcing a liquid, a powder, or a granular polishing agent through an opening of the device using a high-pressure air. Conventional device, therefore, tend to have a structure that forces high-pressure air and/or a cleaning fluid or other medium through a nozzle of the device.
Japanese Patent Publication No. 2001-104840 describes a flexible nozzle made of a flexible cylindrical member and arranged to turn along the inner side of a horn-like guide. Japanese Patent Publication No. 2008-154294 describes a nozzle in which pressurized gas is sprayed together with liquid, while a flexible nozzle having an inside/outside double structure of flexible tube materials, is rotated within a trumpet-shaped control member. The flexible nozzle is made of synthetic resin, such as nylon and polypropylene, and by powerfully spraying the pressurized gas from spray ports of its tip end, a negative-pressure zone is formed there around, and a sub-medium is sucked by the negative pressure, aerosoled, and sprayed against an object to be sprayed together with the pressurized gas. By spraying the pressurized gas from the tip end (free end) of the flexible nozzle, a whole body of this nozzle is rotated due its reaction force, and the tip end draws a circumferential track along an inner circumferential surface of the trumpet-shaped control member. By spraying the pressurized gas while the tip end is rotated and moved, a pressure wave of the sprayed pressurized gas is amplified, thereby increasing a spraying force. The sub-medium is rotated and diffused, thus making it possible to obtain aerosol having a very small diameter. A cleaning device, a painting device, and a blast device, etc, are provided as examples of specific purposes of use of the spray apparatus, and a liquid detergent, paint in a state of liquid or granular solids, and a powdery or granular blast material (granular solids) may be used as the sub-medium.
Such flexible nozzles, however, may have certain limitations. For example, since a significant pressure at the ejection of pressurized air is needed to stably turn the flexible nozzle, the flexible nozzle may be conducive for use in high-pressure applications, but not conducive for use in low-pressure applications, such as a blower for producing a delicate blow of pressurized air. Further, the use of a horn-like guide to constrain the flexible nozzle to produce the turning action at a desired diameter may create a significant amount of contact between the flexible nozzle and the guide. The contact may result in contamination and wearing of each of the components. The resistance to movement due to the wear between the nozzle and the inner side of the guide may increase and reduce the ability of the nozzle to rotate. Further, a flexible nozzle, such as that made of a synthetic resin material, may be susceptible to certain environmental conditions. For example, the flexible nozzle may harden during the winter or in a cold climate, thereby reducing the ability of the nozzle to rotate and lessening the ability to provide the desired dispersion of the pressurized air in a turning movement.